Saturday nights, when his cozy parrillada is just about full, Jorge "Papa Gallo" Sanchez, the Uruguayan owner of Zuperpollo, wedges his burly frame from behind the cash register and onto the restaurant's tiny stage. A big man with a giant personality, Sanchez easily dominates the room when he takes the mike and treats his guests to dramatic interpretations of tangos and folk songs from the pampas and the Rio de la Plata basin. His hearty vibrato easily overtakes the busy flow of waiters and loud conversations beneath the chintzy trellis. The songs are complex enough, with Sanchez hitting all the emotional nuances of the melancholy tunes, that one is glad to let go of dinner conversation to listen. But if you must talk, get there early -- otherwise you will be seated at a table in the middle of the room, and you'll have no choice but to participate in the best place to hear tango.